The present invention relates, in general, to visual inspection of an object and, more particularly, to an apparatus and a process for visually inspecting an object.
Typically, work pieces such as semiconductor devices are visually inspected to insure that they meet design specifications for parameters such as lead coplanarity, lead length, lead straightness, mark inspection, surface inspection, lead pitch, etc. The visual inspection of a semiconductor device is conventionally performed using a visual inspection station. The semiconductor device is placed on the visual inspection station. Using either a front lighting technique or a back lighting technique, the images of the semiconductor device are formed and analyzed using a vision computer. If the semiconductor device meets predetermined design specifications, the device passes the inspection and is moved to the next stage of the manufacturing process. Otherwise, the device is rejected. The conventional visual inspection process disrupts the process of handling the semiconductor device and is often time consuming. Further, it is difficult to incorporate the conventional visual inspection process in an automated device handling process that is both cost efficient and time efficient.
Accordingly, it would be advantageous to have an apparatus and a method for visually inspecting an object in an automated process of handling the object. It is desirable for the method to be simple and time efficient. It is also desirable for the apparatus to be inexpensive. It would be of further advantage for the apparatus to be compatible with existing object handling equipment and process.